Development of a sustainable and antibacterial food packaging material based in a biopolymeric multilayer system composed by polylactic acid, chitosan, cellulose nanocrystals and ethyl lauroyl arginate

Study of the release kinetics of Ethyl Lauroyl Arginate from poly(3-hydroxybutyrate-co-3-hydroxyvalerate) active films

This study investigates the underexplored area of the release mechanism and kinetics of the antimicrobial Ethyl Lauroyl Arginate (LAE®) from an innovative active packaging system based on poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). We evaluated the impact of food simulants and temperatures on LAE® release, diffusion, and partition coefficients. Mathematical modeling was used to elucidate LAE® release kinetics, offering understanding of the release behaviour in food matrices. Results highlighted that temperature notably affected LAE® release into simulant A (10% EtOH) unlike the release into simulant D1 (50% EtOH). Although the release was faster in the less polar simulant, a greater partition coefficient demonstrated greater LAE® retention within the polymer matrix at equilibrium. Weibull models ensured robust fits, suggesting their usefulness for future studies on LAE® release kinetic. Finally, the active films were validated in food, showing significant reduction in microbial counts. These findings contribute to the design of effective antimicrobial food packaging and the selection of suitable food applications.

Improving Crystallization Properties, Thermal Stability, and Mechanical Properties of Poly(L-lactide)-b-poly(ethylene glycol)-b-poly(L-lactide) Bioplastic by Incorporating Cerium Lactate

The more flexible and faster biodegradation rate of poly(L-lactide)-b-poly(ethylene glycol)-b-poly(L-lactide) (PLLA-PEG-PLLA) triblock copolymer makes it a promising bioplastic compared to PLLA. However, finding effective additives for this triblock copolymer remains a research challenge for their wider applications. This work involved the melt-blending of a cerium lactate (Ce-LA) antibacterial agent with a triblock copolymer. The thermal properties, crystalline structures, mechanical properties, and phase morphology of the PLLA-PEG-PLLA/Ce-LA composites were examined. With 0.5 wt% Ce-LA, the composite exhibited the best crystallization properties. The crystallinity of the composite contained 0.5 wt% Ce-LA increased from 11.8 to 15.9%, and the half-time of crystallization decreased from 3.37 to 1.28 min at 120 °C, compared with the pure triblock copolymer. The incorporation of Ce-LA did not result in any changes to the crystalline structure of the triblock copolymer matrix. The best improvement in thermal stability and tensile properties of the composites was achieved with the addition of 1.5 wt% Ce-LA. When compared to the pure triblock copolymer, the temperature at maximum decomposition rate of PLLA blocks shifted from 310 °C to 327 °C, the tensile strength increased from 14.3 MPa to 19.5 MPa, and the Young's modulus increased from 204 MPa to 312 MPa. This study concludes that the incorporation of Ce-LA enhanced the crystallizability, thermal stability, and mechanical properties of PLLA-PEG-PLLA, indicating that Ce-LA could serve as a versatile additive to the PLLA-PEG-PLLA bioplastic.

PLA- and PHA-Biopolyester-Based Electrospun Materials: Development, Legislation, and Food Packaging Applications

The high accumulation of plastic waste in the environment has led to great interest in biodegradable polymers, such as polylactic acid (PLA) or polyhydroxyalkanoates (PHAs). Their benefits, combined with the application of electrospinning technology, represent an innovative proposal for the food packaging industry. This article provides a comprehensive review of the latest developments of PLA- and PHA-biopolyester-based electrospun materials for food packaging applications, summarizing the reported technologies, material properties, applications, and invention patents. In addition, the legislation used to assess their biodegradability is also detailed. Electrospun packaging materials are largely developed through uniaxial, coaxial, emulsion, multiaxial, and needleless techniques. PLA- and PHA-biopolyester-based electrospun materials can be obtained as single and multilayer packaging structures, and the incorporation of natural extracts, organic compounds, and nanoparticles has become a great strategy for designing active food packaging systems. The biodegradability of electrospun materials has mainly been evaluated in soil, compost, and aquatic systems through ASTM and ISO normatives. In this review, the dependence of the biodegradation process on the polymer type, conditions, and test methods is clearly reviewed. Moreover, these biodegradable electrospun materials have shown excellent antioxidant and antimicrobial properties, resulting in a great method for extending the shelf life of fruits, bread, fish, and meat products.

Strong, bacteriostatic and transparent polylactic acid-based composites by incorporating quaternary ammonium cellulose nanocrystals

Renewable natural fibers (e.g., cellulose nanocrystals (CNCs)) are being applied for reinforcing bio-based polylactic acid (PLA). For improvement in the interfacial compatibility between CNCs and PLA and the dispersibility of CNCs, a quaternary ammonium salt-coated CNCs (Q-CNCs) hybrid was prepared in this study based on an esterification self-polymerization method, and such hybrid was further utilized as a new strengthening/toughening nanofiller for producing the Q-CNCs-reinforced PLA composite. The results confirmed that quaternary ammonium salt coatings could efficiently enhance CNCs/PLA interfacial compatibility via mechanical interlocking and semi-interpenetrating networks. Attributing to the synergistic effect of quaternary ammonium salts and CNCs, a considerable enhancement in processing, mechanical, and thermal properties was gained in the obtained Q-CNCs-reinforced PLA composite. With the addition of 0.5 wt% Q-CNCs, the tensile strength, Young's modulus, and elongation at break of the Q-CNCs-reinforced PLA composite was raised by approximately 23 %, 37 % and 18 %, respectively; compared with pure PLA, the obtained composite had excellent bacteriostatic properties and good transparency. This work discusses the development of high-performance, low-cost and sustainable PLA-based composites on a potential application in packaging materials.

A review on bio-based polymer polylactic acid potential on sustainable food packaging

Poly(lactic acid) (PLA) stands as a compelling alternative to conventional plastic-based packaging, signifying a notable shift toward sustainable material utilization. This comprehensive analysis illuminates the manifold applications of PLA composites within the realm of the food industry, emphasizing its pivotal role in food packaging and preservation. Noteworthy attributes of PLA composites with phenolic active compounds (phenolic acid and aldehyde, terpenes, carotenoid, and so on) include robust antimicrobial and antioxidant properties, significantly enhancing its capability to bolster adherence to stringent food safety standards. The incorporation of microbial and synthetic biopolymers, polysaccharides, oligosaccharides, oils, proteins and peptides to PLA in packaging solutions arises from its inherent non-toxicity and outstanding mechanical as well as thermal resilience. Functioning as a proficient film producer, PLA constructs an ideal preservation environment by merging optical and permeability traits. Esteemed as a pioneer in environmentally mindful packaging, PLA diminishes ecological footprints owing to its innate biodegradability. Primarily, the adoption of PLA extends the shelf life of products and encourages an eco-centric approach, marking a significant stride toward the food industry's embrace of sustainable packaging methodologies.

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Formulation and application of poly lactic acid, gum, and cellulose-based ternary bioplastic for smart food packaging: A review

In future, global demand for low-cost-sustainable materials possessing good strength is going to increase tremendously, to replace synthetic plastic materials, thus motivating scientists towards green composites. The PLA has been the most promising sustainable bio composites, due to its inherent antibacterial property, biodegradability, eco-friendliness, and good thermal and mechanical characteristics. However, PLA has certain demerits such as poor water and gas barrier properties, and low glass transition temperature, which restricts its use in food packaging applications. To overcome this, PLA is blended with polysaccharides such as gum and cellulose to enhance the water barrier, thermal, crystallization, degradability, and mechanical properties. Moreover, the addition of these polysaccharides not only reduces the production cost but also helps in manufacturing packaging material with superior quality. Hence this review focuses on various fabrication techniques, degradation of the ternary composite, and its application in the food sector. Moreover, this review discusses the enhanced barrier and mechanical properties of the ternary blend packaging material. Incorporation of gum enhanced flexibility, while the reinforcement of cellulose improved the structural integrity of the ternary composite. The unique properties of this ternary composite make it suitable for extending the shelf life of food packaging, specifically for fruits, vegetables, and fried products. Future studies must be conducted to investigate the optimization of formulations for specific food types, explore scalability for industrial applications, and integrate these composites with emerging technologies (3D/4D printing).

Chitosan-Based Films Blended with Tannic Acid and Moringa Oleifera for Application in Food Packaging: The Preservation of Strawberries (Fragaria ananassa)

Biobased plastics provide a sustainable alternative to conventional food packaging materials, thereby reducing the environmental impact. The present study investigated the effectiveness of chitosan with varying levels of Moringa oleifera seed powder (MOSP) and tannic acid (TA). Chitosan (CS) biocomposite films with tannic acid acted as a cross-linker, and Moringa oleifera seed powder served as reinforcement. To enhance food packaging and film performance, Moringa oleifera seed powder was introduced at various loadings of 1.0, 3.0, 5.0, and 10.0 wt.%. Fourier-transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy analyses were performed to study the structure and morphology of the CS/TA/MOSP films. The scanning electron microscopy results confirmed that chitosan/TA with 10.0 wt.% of MOSP produced a lightly miscible droplet/matrix structure. Furthermore, mechanical properties, swelling, water solubility, optical barrier, and water contact angle properties of the film were also calculated. With increasing Moringa oleifera seed powder contents, the biocomposite films' antimicrobial and antifungal activity increased at the 10.0 wt.% MOSP level; all of the observed bacteria [Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), Aspergillus niger (A. niger), and Candida albicans (C. albicans)] had a notably increased percentage of growth. The film, with 10.0 wt.% MOSP content, effectively preserves strawberries' freshness, making it an ideal food packaging material.

Synthesis and Applications of Hybrid Polymer Networks Based on Renewable Natural Macromolecules

Macromolecules obtained from renewable natural sources are gaining increasing attention as components for a vast variety of sustainable polymer-based materials. Natural raw materials can facilitate continuous-flow production due to their year-round availability and short replenishment period. They also open new opportunities for chemists and biologists to design and create "bioreplacement" and "bioadvantaged" polymers, where complex structures produced by nature are being modified, upgraded, and utilized to create novel materials. Bio-based macromonomers are expected not only to compete with but to replace some petroleum-based analogs, as well. The development of novel sustainable materials is an ongoing and very dynamic process. There are multiple strategies for transforming natural macromolecules into sophisticated value-added products. Some methods include chemical modification of macromolecules, while others include blending several components into one new system. One of the most promising approaches for incorporating renewable macromolecules into new products is the synthesis of hybrid networks based on one or more natural components. Each one has unique characteristics, so its incorporation into a network brings new sustainable materials with properties that can be tuned according to their end-use. This article reviews the current state-of-the-art and future potential of renewable natural macromolecules as sustainable building blocks for the synthesis and use of hybrid polymer networks. The most recent advancements and applications that involve polymers, such as cellulose, chitin, alginic acid, gellan gum, lignin, and their derivatives, are discussed.